v3.3.1.900
Income Taxes Unrecognized Tax Benefits Roll Forward (Details) - USD ($)
$ in Millions
12 Months Ended
Dec. 31, 2015
Dec. 31, 2014
Dec. 31, 2013
Income Tax Disclosure [Abstract]      
Uncertain Tax Positions More Likely Than Not Largest Amount of Benefit Percentage 50.00%    
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward]      
Balance at beginning of period $ 57 $ 61 $ 74
Additions related to current year 9 11 0
Additions related to prior year 0 0 16
Reductions related to prior year (15) (7) (25)
Reductions due to expirations of statute of limitations 0 (6) (4)
Settlements (3) (2) 0
Balance at end of period 48 57 61
Income Tax Uncertainties [Abstract]      
Unrecognized Tax Benefits that Would Impact Effective Tax Rate 35 32  
Unrecognized Tax Benefits that Would Impact Effective Tax Rate, Write off of Related Deferred Tax Asset 15 25  
Unrecognized Tax Benefits, Income Tax Penalties and Interest Accrued 11 12  
Unrecognized Tax Benefits, Income Tax Penalties and Interest Expense (Benefit) $ 1 $ 3 $ 3